-9a^2+54a-45=0

Solution for -9a^2+54a-45=0 equation:

-9a^2+54a-45=0

a = -9; b = 54; c = -45;
Δ = b2-4ac
Δ = 542-4·(-9)·(-45)
Δ = 1296
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1296}=36$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(54)-36}{2*-9}=\frac{-90}{-18}
=+5
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(54)+36}{2*-9}=\frac{-18}{-18}
=1
$